A beam: need to calculate its max moment and deflection

Click For Summary
SUMMARY

The discussion focuses on calculating the maximum moment and deflection of a beam spanning 40 feet, subjected to a uniform load of 500 pounds per foot and a point load of 4000 pounds at mid-span. The beam is supported by a roller at Support A and a pin at Support B. The Force method is utilized to determine the maximum moment and deflection, employing the unit load method for deflections. Key equations include Delta + f F = 0, with Delta representing deflection and f representing the virtual force.

PREREQUISITES
  • Understanding of beam mechanics and structural analysis
  • Familiarity with the unit load method for deflection calculations
  • Knowledge of integration techniques in engineering mathematics
  • Experience with determining moments in statically determinate structures
NEXT STEPS
  • Study the application of the unit load method in beam deflection analysis
  • Learn about calculating reactions and moments in statically determinate beams
  • Explore the integration of moment functions for deflection calculations
  • Review examples of virtual work principles in structural analysis
USEFUL FOR

Structural engineers, civil engineering students, and professionals involved in beam analysis and design will benefit from this discussion.

Poke

Homework Statement


Beam spans 40 feet, with uniform loading of 500 pound/feet and a point load of 4000 pound at mid span.
Support A is roller, support B is pin.
How to determine the maximum moment and maximum deflection due to the loads.
Use Force method

4-24-2018 18-46 Office Lens (8).jpg


Since it is a Determinate structure, I am not very sure how to use the method.

Homework Equations


Delta + f F = 0

find Delta

The Attempt at a Solution


I suppose I need to add a virtual force of 1 pulling the structure down at mid span... so that it generates 2 virtual moments (m).

From the original structure, I can also get 2 real moments (M).

Then using the equations:

Delta = integration of m*M / EI ...
f = integration of m*m / EI

And then I will know deformation??
 

Attachments

  • 4-24-2018 18-46 Office Lens (8).jpg
    4-24-2018 18-46 Office Lens (8).jpg
    9.3 KB · Views: 552
Physics news on Phys.org
I guess that's the unit load method for determining deflections. When calculating M and m you need to show it as a function of x.
And since fthe applied and virtual point loads result in a discontinuity In moment, you have to write 2 equations for the moments, one for the left side of center, and one for the right. Then do the integrations and add them all up
 

Similar threads

  • · Replies 8 ·
Replies
8
Views
2K
  • · Replies 3 ·
Replies
3
Views
2K
  • · Replies 2 ·
Replies
2
Views
2K
  • · Replies 3 ·
Replies
3
Views
4K
Replies
1
Views
2K
  • · Replies 1 ·
Replies
1
Views
2K
  • · Replies 1 ·
Replies
1
Views
3K
  • · Replies 11 ·
Replies
11
Views
3K
Replies
5
Views
2K
Replies
6
Views
2K